S-acyloxyalkyl and s-acyloxyalkenyl esters of o, o-diorgano-phosphorothiolic acids



United States Patent "Ice 3,166,581 S ACYLOXYALKYL AND S ACYLOXYALKENYLESTERS 0F 0,0 DIGRGANO PHOSPHORGTHI- OLIC ACIDS 1 'Geert C. Vegter,Horne Bay, Kent, England, assignor to Shell Oil Company, a corporationof Delaware No Drawing. Fiied Nov. 13, 1959, Ser. No. 852,604 Claimspriority, application Great EritaimJuly 18, 1958,

23,137/58; Dec. 23, 1958, 41,489/58 9 Claims; (Cl. 260-456) Thisapplication is a continuation-in-part of my copending application SerialNo. 826,442, filed July 13, 1959, and now abandoned.

This invention relates to novel phosphorus-containing esters, valuableas insecticides, and suitable in particular for use as plant-protectingagents.

These new insecticides are the S-acyloxyaliphatic esters of 0,0-diestersof phosphorothiolic acids, including phosphorothiolothionic acidswherein each of the ester groups bonded to oxygen is a monovalent group,being charac terized by the structure of an acyloxyaliphatic radicalbonded via the thiolo sulfur atom to the phosphorus atom ofphosphorothiolic acid, or of phosphorothiolothionic acid. The newinsecticides are characterized by the structural formula:

RO X

i -s-a-o-ac i R'-0 wherein R represents a divalent aliphatic radical,each of R represents a monovalent organic groupwhich may be the samegroup, different groups of the same kind, or different kinds ofgroupswhich is the residue of an alcohol, R'OH, X represents oxygen orsulfur, and acyl represents an acyl residue of an acid.

Preferably, R represents hydrocarbon of up to ten carbon atoms-that isto say, each of R is a hydrocarbon group, both of the groups togethercontaining up to'10 carbon atomsor such hydrocarbon groups substitutedby one or more nitro groups, one or more halogen atoms or one or morealkoxy groups of up to four carbon atoms. The groups represented by Rmay suitably be straight chain, branched chain or cylic inconfiguration; they may be saturated, olefinically unsaturated oraromatically unsaturated. Preferably, they are free from acetylenicunsaturation. Suitable groups thus include the alkyl grougs, thecycloalkyl groups, aralkyl groups, alkaryl groups, aryl groups, alkenylgroups, alkadienyl groups, cycloalkenyl groups, aralkenyl groups,alkenylaryl groups, and the like. The most useful of the new class ofcompounds are believed to be those wherein R represents an alkyl groupof up to eightcarbon atoms, the phenyl group, a nitro-phenyl group, or ahalophenylgroup.

The aliphatic group represented by the symbol, R,

preferably contains only carbon atoms in the chain bonding the indicatedsulfur atom to the indicated oxygen atom. These carbon atoms may all besaturated carbon atoms, or two or more may be olefinically unsaturated;preferably, none are acetylenically unsaturated. Where olefinicunsaturation is present in the chain, preferably one olefinicallyunsaturated pair of carbon atoms consists 3,l%,5l Patented Jan. 19, 1965of the alpha and beta carbon atoms relative to the indicated sulfuratom. The carbon chain may be substituted, the preferred substituentsbeing selected from halogen atoms, the cyano group, the nitro group,amino groups and monovalent hydrocarbon substituent groups such as arerepresented by the symbol R. Desirably, the group R contains no morethat ten carbon atoms, with no more than six carbon atoms in the chainbonding together the indicated sulfur and oxygen atoms, and it ispreferred that the group R contain no more than about six carbon atoms,with no more than four carbon atoms in the chain.

In the formula, acyl is the acyl group of an acid.

By acyl group is meant the organic radical derived from an organic acidby the removal of the hydroxyl group. In the case of a carboxylic acid,RC(O)-OH, the acyl group is: R"C(O), while inthe case of a sulfonicacid, R-SO OH, the acyl group is: R"SO Suitably, the acyl group may bethat of an aliphatic carboxylic acid, an aliphatic sulfonic acid(R=aliphatic), a haloaliphatic carboxylic acid, a haloaliphatic sulfonicacid (R=haloaliphatic), a phenyl carboxylic acid, a phenyl sul-fonicacid (R"=phenyl), or a substituted phenyl carboxylic acid, a substitutedphenyl sulfonic acid (R=substituted phenyl, preferred substituents beinghalogen, nitro and alkoxy of up to four carbon atoms), an aliphaticcarbonic acid (R"=aliphatic- \oxy), a phenyl carbonic acid (R =phenyloxy), an amino acid (R:aminoalkylene, or, preferably (R3) N-- alkylene,wherein R =H or R), a carbamic acid (R"=amino, or, preferably, (R N),phosphoric acid, a mo-noester or digester thereof a phosphonic acid orester thereof -i ono or a phosphinic acid or their sulfur analogs.Preferably, the acyl group contains no more than ten carbon atoms.

In these acyl groups, the aliphatic groups preferably contain onlycarbon in the chain, and maybe either saturated or olefinicallyunsaturated; preferably, they are free. from acetylenic unsaturation.Preferably, each aliphatic group contains not more than 4 carbon atoms.

. Hydrocarbon aliphatic groups (i.e., alkyl, alkenyl, and

both saturated and olefinically unsaturated alkylene groups), and thesegroups substituted by halogen, are.

As will be evident from the foregoing, there are seven subgenera of thenew genus of insecticides which are of particular interest, as follows:

(1) The S-acyloxyalkyl ester of an 0,0-dialkyl ester of aphosphorothiolic acid, including phosphorothiolothionic acids, Where theacyl group is that of a carboxylic acid, this subgenus having theformula:

alkyl-O X II II PS-alkylene-OC-hydrogen, alkyl or aryl alkyl-O (2) TheS-alkyloxyhaloalkyl ester of an 0,0-dialkyl ester of a phosphorothiolicacid, including phosphorothiolothionic acids, where the acyl group isthat of a carboxylic acid, this subgenus having the formula:

alkyl-O X II II P-S-haloalkylcne-OC-l1ydrogen, alkyl or aryl alkyl- (3)The S-acyloxyalkenyl, including haloalkenyl, ester of an 0,0-dialkylester of a phosphorothiolic acid, in-

cluding phosphorothiolothionic acids, where the acyl group is that of acarboxylic acid, this subgenus having the formula alkyl-O X R i SJ=C-alkylene-O hydrogcn, alkyl or aryl alkyl-O R (4) TheS-halocycloxyalkyl ester of an 0,0-dialkyl ester of a phosphorothiolicacid, including phosphorothiolothionic acids, where the acyl group isthat of a carboxylic acid, this subgenus having the formula:

alkyl-O I]? (I) P- S -alkylene-O -haloalkyl alkyl-O.

(5) The S-acyloxyalkyl ester of an 0,0-dialkyl ester of aphosphorothiolic acid, including phosphorothiolothionic acids, where theacyl group is that of a sulfonic acid, this subgenus having the formula:

is that of a carboxylic acid, this subgenus having the formula:

alkyl-O X (I) P- S -haloalkylene'O( l-hydrogen or alkyl nitrophenyl-O(8) The S-acyloxyalkyl ester of an O-alkyl, O-halogensubstituted phenylester of a phosphorothiolic acid, including phosphorothiolothionicacids, where the acyl group is that of a carboxylic acid, this subgenushaving the formula halophcnyl-O X 0 P- S -haloalkylene-O-(i-hydrogen oralkyl alkyl-0 wherein X is oxygen or sulfur, alkyl is an alkyl group lof from 1 to 4 carbon atoms, haloalkyl is an alkyl group (as definedherein) substituted by from one to a plurality of halogen atoms,haloalkylene is an alkylene group (as defined herein) substituted byfrom one to a plurality of halogen atoms, alkylene is an alkylene groupof from 1 to 6 carbon atoms With from 1 to 4 carbon atoms in the chainlinking together the indicated sulfur and oxygen atoms, aryl is amono-nuclear aromatic hydrocarbon group of from 6 to 10 carbon atoms(that is, aryl is the phenyl group or alkyl-substituted phenyl groupswherein the alkyl group or groups contain up to 4 carbon atoms),halophenyl is a phenyl group substituted from one to a plurality ofhalogen atoms, and R is hydrogen, halogen, alkyl of l to 4 carbon atoms,or phenyl, and these subgenera 1-6, Where one or both of the alkylgroups bonded by oxygen to phosphorus is replaced by a phenyl group.

These new insecticides can be prepared by various processes, which arefurther features of this invention.

(A) According to one process, the compounds may be prepared by reactinga phosphorus oxyor thio-halide P(X) (halogen) for example, phosphorusoxychloride or phosphorus thiochloride, with a partial acyl ester,

R and acyl having the respective meanings set out hereinbefore,preferably in the presence of a hydrogen halide acceptor, or with asalt, preferably an alkali metal salt, of said ester, to produce anintermediate compound,

This intermediate then is reacted with a hydroxy compound or compounds,ROH, R having the meaning set out hereinbefore, preferably in thepresence of a hydrogen halide acceptor, or with a salt, preferably analkali metal salt of said hydroxy compound(s), to give the desiredproduct.

(B) In an alternative, preferred process, the compound is reacted insimilar fashion with the partial ester,

HSRO-acyl or a salt thereof, to produce the desired end product, or witha thiolalcohol,'I-ISROH, or with a salt thereof, MSROH (where Mrepresents a salt-forming atom or group, preferably alkali metal orammonium) to produce an intermediate of formula it ROPSR0H which thencan be converted to the acyl ester, for example, by treatment with theappropriate acid, acylOI-I, or acid chloride, acylOCl, or acidanhydride,

acyl-O-acyl or by ester interchange with an ester of such acid with avolatile alcohol. In the foregoing descripiton, all of the symbols havethe respective meanings already set out hereinbefore.

(C) According to a further, also preferred, process, a salt of thediester is reacted with a partial acyl ester of formula,

Z-RO-acyl wherein Z represents an atom or group which is split off inthe reaction, preferably being a halogen atom, an alkyl sulfuric acidester, or aryl-sultonate group, to produce the desired end product.

(D) The novel compounds of the invention may also be prepared accordingto another, also preferred, process by reacting a diester of formula Ina similar manner, addition occurs to an acetylenic linkage to produce acompound'in which the group R is olefinically unsaturated. Thus,reaction with the acetate of Z-propynol can be expressed by theequations:

Examples of olefinic and acetylenic alcohols whose esters may be used inthe above addition reaction are the esters of vinyl alcohol, CH =CHOH,allyl alcohol, CH =CHCH OH, Z-butenol, .CH -CH CH OH, 3-buten-2-ol, CH=CHC(CH )HOH, 3-butenol,

cinnamyl alcohol, phenylCH=CI-lCH-;OH, 2-pr0- pynol, CHECCH2OH,3-butyn-2-ol,

CHEC--C(CH )HOH 1-phenyl-prop-1-yn-3-ol, phenyl-CHE CCH OH, and thelike. These alcohols may be substituted by the atoms or groups alreadyset out herein as substituents whcih may be present in the groupsrepresented by R.

(E) Another, and preferred, process for preparing compounds of theinvention employs as starting materials, a new class of compounds havingthe formula:

wherein the halogen preferably is chlorine, bromine or fluorine,chlorine being particularly preferred. These new compounds and themethod for their preparation form the subject matter of my US. PatentNo. 3,081,329. In this process, a compound of the foregoing class isreacted with an ester of an olefinically or acetylenically unsaturatedalcohol and the resulting phosphorochloridothionate is reacted withahydroxy compound R'OH. If it is desired that both groups R'in' thefinal productbe the same, then R of the hydroxy compound is the same asR of'the phosphorochloridothionate; if desired, then'the groups, R, canbe different. The reaction sequence is illustrated by the equations:

All of the reactions set out above should be carried out under anhydrousconditions. An inert solvent, such as ether, halogenated hydrocarbonssuch as carbon tetrachloride, or aliquid aliphatic or aromatichydrocarbon, such as hexane, benzene, xylenes or the like, may beemployed to advantage in some cases, but may be omitted if one or moreof the reactants are liquid. The addition reactions to unsaturatedcompounds in some cases proceed vigorously, usually after an inductionperiod of' a few minutes; in other cases, it may be necessary to add asmall amount of a suitable catalyst which provides or causes generationof free radicals. The usual generators of free radicals such as actinicradiation and organic peroxides, such as benzoyl peroxide, are suitable.These addition reactions are preferably effected initially at belowabout 40 C., with the reaction mixture eventually being heated at about70 C. to C. for about an hour to insure completion of the reaction. Theother reactions described above are, in general, eifected at about 70 C.to 80 C. Reactions involving evolution of a hydrogen halide arepreferably effected in the presence of a hydrogen halide acceptor, anorganic tertiary nitrogen base such as pyridine or an alkyl pyridinebeing preferred for this purpose.

When reaction is complete, any precipitate formed can be filtered offand any solvent or other volatile material removed by distillation,preferably under reduced pressure. The residual esters are in generalliquids. Some are sufficiently heat-stable to allow distillation in ahigh vacuum. Less stable liquids can be purified by thorough washingwith water, drying and Warming in a high vacuum to remove volatileimpurities. Solid esters can be purified by recrystallization.

In describing the foregoing processes for preparing the compounds of theinvention, extended descriptions of the suitable reactants, includinglisting of numbers of species of the suitable reactants, have not beenincluded because it is felt that such extended descriptions Would beundesirable because they would increase the length of this specificationand the complexity of descriptions of the processes without serving anyuseful purpose, and such detailed descriptions are believed unnecessaryto understanding of the performance of those processes. The reactants,accordingly, have been described in terms of their general structure, itbeing intended that detailed descriptions are provided by means of thevarious symbols 8 EXAMPLE 2 Preparation of 0,0-diethyl-S-Z-chloroacefoxyethyl phosphorothiolate used, the meanings of those symbols having beenset out 021-150 illllegigzilitilln the description of the new compoundsof i The following examples-illustrate the novel compounds CZHBO of theInvention and a process for their preparation, the Diethylphosphorochlon-date (1725 Pbw'; 01 mol) Part? by Welght and Part? byvolume (Pb-VJ was mixed with 2-mercaptoethyl chloroacetate (15.45bearing the same relation as the kilogram bears to the 1 l), To thestirred mi Py hterp.b.w.; 0.1 mol) was gradually added. Some heat wasEXAMPLE 1 evolved and the temperature was kept below 50C. by Preparationof 0,0-diethyI-S-Z-acetoxyethyl external cooling. Some pyridinehydrochloride separated. phosphorothiolate When the exothermic reactionceased, the mixture was 0 H50 0 heated in a water bath to 70 C. forminutes and left 2 overnight. The next day, the reaction mixture was ex-P-S CHPCHZOC(O)CH3 :tracted with ether and the ether extract washed with0 11 0 Water and dried over anhydrous sodium sulfate. The A solution of2,6-lutidine 107 p.b.w.; 1 mol) in dry t e P other Pmducts W? rammed byether (500 Pb) was added slowly to a mixture of distlllatron, eventuallyunder 0.05 mllllmeter mercury mercaptoethyl acetate (120 Pbwd 1 mol) andpressure and a bath temperature of 80 C. The residue ethylphosphorochloridate (173 p.b.w.; 1 mol) dissolved consist; ofoo'dlethyl's'z'chloroacetoxyethyl Phos' in dry ether (1000 p.b.v.) in avessel fitted with reflux 2r phgfothlolate' condenser, stirrer and inlettube and cooled externally in 0 hnumber of compounds. plepfuedaccording. to mhe ice. During the addition, a white precipitate of 2,6-f; of Example 2 are m Table I Whlch also lutidine hydrochloride wasformed. After addition was gives e thlol ester reacted Wlth the compoundcomplete, the mixture was allowed to stand for about one X hour, theprecipitate was filtered off and the filtrate dis- 30 (W0) {L tilled toremove the ether. The residue was then dis- 2 tilled under reducedpressure in an atmosphere of nitro- Wh r R represents a methyl or ethylgroup and X repregen yielding after a forerun of unreacted startingmatesents an oxygen or sulfur atom. The table also gives the rials, thedesired ester, 0,0-diethyl-S-2-acetoxyethyl phosyield and analyticaldata of the products. The correphorothiolate, boiling point 9294 C. at0.01 millimeter sponding data for the compound of Example I is alsomercury pressure. Yield 60%. included.

TABLE I Product Analysis Ex- Found Calculated Yield, ample CompoundThlol Ester Starting Materlal percent of No. Theory Per- Per- Per- Per-Per- Percent cent; cent cent cent cent 0 H s o H s 1 0,0-DiethylS-2-acetoxyethyl phosphorothiolate HSCHzCH2OC(O)-CH3 36.2 7.0 11.9 37.56.6 12.5 15

PSCH2OHzO-O(O)-CH3 2 ofi liiiesthyl S-Z-ehloraoeetoxyethyl phosphoro-HSCH2CHzO-C(O)CHzCl 34.2 5.7 11.4 33.0 5.5 11.4 35

1O 3 e. C2HsO\(") P-SCH2-CHzOC(O)-CH;7CI

3 0,0-Diethyl S-2-is0butyryl0xyethyl phos HS-CHz-CHz-O-C(O)-CH(CHa)z21.7 21.3 16

phorodithioate. 02H50\fi P-S-CHrCHz0C(O)-CH(CH:)1

4 O,t(l)1:I;i!tnethy1 S-Z-aeetoxyethyl phosphoro- HS-CH -CH -OC(O)CH331.4 5.8 13.8 31.6 5.7 14.0 13

PSCHzCH2-OC(O)CH CHsO 5 0,0-Diethyl S-2-isobutyryloxyethyl phos-HS-CHz-CHz-OO(O)CH(CH;;) 43.5 7.7 10.8 42.3 7.4 11.3 31

phorothiolate.

CzHaO O 02BX30 V, i

' sodium sulfate.

TABLE I-Oontinued Product Analysis Ex- Found Calculated Yield, ampleCompound Thiol Ester Starting Material percent of No. g Theory Per- Per-Per- Per- Per- Percentcent cent .cent cent cent 0 H S O H S 6 O,t(l);Dli%thyl S-Z-benxoyloxyethyl phosphoro- HS-CHz-CHzO-C(O) 47.5 5.9 9.9 49.06.0 10.1

C9H5O O 7 \ll /PSCH2-CHz-OC(O) CzHsO EXAMPLE 7 EXAMPLE 9 P 17 foio-diefltyloflcetoxymethyl Preparation of 0,0-dielhylS-2-acet0xy-2-c71l0r0ethy! phosplwrodlthwate phosphorothiolme 2Ha0\fiCQHSO 3-CHr-O-C (O) GH r-s-om-orroi-o-o 0 JH 02H) 0,H 0

A solution of chloromethyl acetate (10.85 p.b.w.; 1 I mol) in acetone(20 p'b) was added to a Stirred Solu A solution of0,0-d1ethylphosphorothiollc chloride tion of 0,0-diethyl-S-potassiumphosphorodithioate (20.8 0 p.b.w.; 1 mol) in acetone (100 p.b.w.) atroom tempera- I] ture. The mixture was allowed to stand overnight and(CZH5O)QPSC1 potassium chloride separated. The following day it wasrefluxed for four hours. The potassium chloride was removed byfiltration and the acetone was removed from the filtrate by evaporationunder reduced pressure and other volatile material was removed bydistillation under 0.3 millimeter mercury pressure and at a bathtemperature of 50 C. The residue was dissolved in ether, the etherealsolution was washed with water and then dried over anhydrous sodiumsulfate. The ether was then removed under reduced pressure, leaving aresidue of 0,0-diethyl O-acetoxymethyl phosphorodithioate. The thionostructure was confirmed by infrared analysis. Yield: 17 p.b.w.

(66%). Analysis.Found; C, 32.8; H, 6.0; S, 24.9%. C H O S P requires C,32.6; H, 5.8; S, 24.9%.

EXAMPLE 8 Preparation of 0,0-dimethyl-S-acetoxymethylphosphorodithz'oate CH3O fi P''SOHgO-C(O)GH3 A solution of chlor-omethylacetate (10.85 p.b.w.; '1 mol) in acetone.(10 p.b.v.) was added withstirring to a solution of 0,0-dimethyl-S-potassium phosphorodithioate(19.6 p.b.w.; 1 mol) in acetone (100 p.b.v.). The mixture was allowed tostand overnight and potassium chloride separated. The following day iswas refluxed for five hours. The potassium chloride was removed byfiltration and the filtrate was concentrated to 30 p.b.v. On addition ofwater (200 p.b.v.) an oil separated. The oil was washed with water anddried over anhydrous Distillation under reduced pressure gave 10 p.b.w.(66% yield) of 0,0-dimethyl S-2-acetoxymethyl phosphorodithioate, Bl.100 C. under 0.02 millimeter mercury pressure. Analysis.--Found: C,26.5, H, 4.8; S, 28%, C H O PS requires C, 26.1; H, 4.9; S, 27.8%.Examples illustrating the preparation of compounds (a) By reacting thecompound P(X)SY R20 with an ester of an unsaturated alcohol.

(10.2 p.b.w.; 0.05 mol) in benzene (10 p.b.v.) was added to a stirredsolution of vinyl acetate (4.3 p.b.w.; 0.05 mol) in benzene (20 p.b.v.)at 30 C. No heat was evolved. The mixture was irradiated withultraviolet light and after three hours was nearly colorless. It wasthenwashed with water and dried over anhydrous sodium sulfate. Onevaporation under reduced pressure, finally at 0.013 millimeter mercurypressure and a bath temperature of C., a residue (10.1 p.b.w.) was leftconsisting of 0,0-diethyl S-2-acetoxy-2chloroetbyl phosphorothiolate.

In an analogous way, the other compounds specified in Table II wereprepared from 0,0-diethylphosphorothiolic chloride and the statedunsaturated esters. Table II also gives the percentage yields andanalytical data for the compounds prepared by this process.

(b) By reacting the compound with an ester of an unsaturated alcohol.

EXAMPLE 17 Preparation of 0,0-Dimethyl S-Z-AcetoxyethylPhosphorodithioate A mixture of 0,0-dimethyl S-hydro genphosphorodithioate (CH O) P(S)SH (7.9 p.b.w.; 0.05 mol) and allylacetate (5.0 p.b.w.; 0.05 mol) was heated with benzoyl peroxide (0.01pib.w.) for 24 hours at 70 C.

Vacuum distillation of the reaction mixture yielded 0,0-dirnethylS-Z-acetoxyethyl phosphorodithioate with RP. 83 C. at 0.09 millimetermercury pressure. By

similar processes, a number of compounds were prepared by. reacting0,-O-dimethyl or 0,0-diethyl S-hydrogen phosphorodithioate with anunsaturated ester. These are summarized in Table 111.

TABLE III Product Analysis Example Unsaturated Ester Starting FoundCalculated Yield,

No. Compound M aterial Percent of Theory Per- Per- Per- Per- Per-Percent cent cent cent cent cent H S C H S 17O,O-Dimet11ylS-2-acetoxyethylphosphorodithioate. HzC=CH-OC(O)CH3 30.3 5.6 26. 4 29. 5 5.3 26.2 52

(CHsO)gP(S)SCH2CH2-OC(O)CH3 i p 18 O,t(l Ditmethyl S-Z-propionyloxyethylphosphorodi- H2C=CH-O-O(O)C2H5 33.1 6.0 25. 6 32. 6 5.8 24.9 90

noa e.

(CI'IsO)z'P(S)s-CII2-CH3-O-C(O)-G2 I5 V 19 0,0-DiethylS-Z-acetoxyethylph0sph0r0ditl1i0ate H2C=CE-0-C(O)-CH 35.0 6. 6 23.7 35.3 6.3 23. 5 90 (C2H50)2P(S)-S-CIIz-CI z-O-C(O)-CI 3 Q 20OhQtZEiet'hylS-2-pr0pionyloiwetl1ylphosphoro- H2C=CI'I-0-O(O)-C2H5 37.06.8 22.7 37.8 6.6 22.7 95

(O H O)1-P(S)-S-CHz-CHg-O-C(O)-C2H5 EXAMPLE 21 EXAMPLEv 22 Preparationof O-ethyl O-p-nitrophenyl S-Z-chloro-Z- propionyloxyethylphosphorolhiolate P'SCH -CHCl-O-C (O)C2H5 C 2H5 O (a) Preparation of theintermediate O-ethyl S-2-chl0r0- Z-propz'onyloxyethylphosphorochloridothionate 0 C H50-i"SCI-I2OHCl-O-C (O)C 1-15 Sulfurylchloride (48.5 p.b.w.; 0.3 mol) was added with stirring to diethylphosphorochloridotliionate (56.6 p.b.w.; 0.3 mol) the reactiontemperature being kept below C. After the addition was complete,stirring was continued for a further 30 minutes at -l0 C. Vinylpropionate (3O p.b.w.; 0.3 mol) was then added with stirring, thetemperature being kept at -l0 C. during the addition. The reactionmixture was then allowed to come to room temperature and the ethylchloride and sulfur dioxide formed were removed by distillation at 13millimeters mercury pressure from a bath at room temperature. Theresidue in the vessel consisted of the desired intermediate (98% yield).

(b) Preparation of O-ethyl-O-p-nitroplzenyl S-Z-chloro-2-pr0pionyloxyethyl phosph0T0thi0late.The intermediate prepared in (a)(29.5 g.; 0.1 mol) was added to p-nitrophenol (13.9 p.b.w.; 0.1 mol) and1,2-dichloroethane (5O p.b.v.) added to aid solution of the phenol.Pyridine (7.9 p.b.w.; 0.1 mol) Was then added with stirring, thetemperature of the exothermic reaction being kept below 40 C. byexternal cooling. When addition was complete, the reaction mixture waswarmed to 65 C. and kept at this temperature for minutes. After standingovernight, the mixture was diluted with 1,2 dichloroethano (500 p.b.v.)and this solution was washed once with water, twice with 5% aqueoussodium bicarbonate solution and again with water and then dried overanhydrous magnesium sulfate. 'The solvent and other lowboiling productswere removed by distillation under reduced pressure, finally at 0.064millimeter mercury pressure and a bath temperature of 60 C. The residue,a viscous brown oil, consisted of O-ethyl O-p-nitrophenylS-2-chloro-2-propi0nyloxyethyl phosphorothiolate. Yield, 12 p.b.w.Analysis.-Found: N, 3.7; S, 3.4; Cl, 8.4%. C H O NSClP requires N, 3.5;S, 8.1; Cl, 8.9%. In a similar way was prepared the o-nitrophenylderivative.

Preparation of O-ethyl O-2,4 dichlorophenyl S-Z-chloro-2-pr0pi0nyloxyethyl phosphorothiolate O-ethyl S-2-chloro-2propionyloxyethyl pho-sphorochloridothionate prepared as described inExample 21(a) (29.5 p.b.w.; 0.1 mol) and 2,4-dichlorophenol (16.3p.b.w.; 0.1 mol) were dissolved in benzene (50 p.b.v.). To this solutionwas added pyridine (7.9 p.b.w.; 0.1 mol) with stirring, the reactiontemperature being kept below 40 C. When the addition was complete, themixture was warmed to C. and kept at this temperature for 15 minutes.After standing overnight, benzene (600 p.b.v.) was added and thesolution washed twice with water and dried over anhydrous sodiumsulfate. The benzene and other volatile products were removed bydistillation under reduced pressure,finally at 0.003 millimeter mercurypressure and a bath temperature of C. The residue, a dark brown oil,consisted of O-et'nyl O-2,4 dichlorophenyl S-2 chloro 2propionyloxyethyl phosphorothiolate. Yield, 23 p.b.w. (58%). Analysis.Found: C, 39.1; H, 3.9; S, 6.9; Cl, 27.0%. C H O SCI P requires C, 37.0;H, 3.8; S, 7.6; Cl, 25.3%. In a similar way the 2- chloro-3,4-dichloroand 2,4,5-triphenyl derivatives were prepared.

The invention provides insecticidal compositions which are characterizedby high toxicity towards insects, but

tions and dispersions of the active ingredients in a suitable liquidcarrier, these compositions being suitable for application in the formof sprays or (lips, or by means of brushing. Suitable liquid carriersare those which are Well-known in the art to be non-toxic to plants, andinclude such materials as kerosene, or similar light mineral oildistillates of intermediate viscosity and volatility. In addition tosuch carriers, other adjuvants may be employed to enhance theeliectiveness of the toxic materials. Such other adjuvants includespreading or wetting agents such as fatty acid soaps, rosin salts,saponins, gelatin, casein, or other proteinaceous material, or syntheticwetting agents of the type of sulfates of long-chain fatty alcohols,alkyl aryl sulfonates, long-chain alkyl sulfonates', phenol-ethyleneoxide condensates, C to C amines, and the like. The solution of thetoxic material may be dispersed or emulsified in water, and the r ltingdispersion or emulsion applied as the spray.

The new insecticidal compositions may be in the form of finely dividedsolids, the active material being combined with a finely divided solidcarrier such as talc, bentonite, lime, gypsum, pyrophillite or the like.The compositions may also contain sticking agents, emulsifying agents orother materials which enhance the effectiveness of the toxic materials.

If desired, the composition may be in the form of an aerosol, the toxicmaterial being dispersed into the air, or atomized into a spray, bymeans of a compressed gas.

The new insecticides provided by this invention are effective systemicpoisons. According to this invention, compositions containing thesetoxic materials are used as systemic insecticides by applying them tothe soil in the vicinity of the growing plant which it is desired toprotect, or directly to the plant itself, the toxic material beingabsorbed by the plant and distributed throughout the tissues thereof,with the result that the plant as a whole acquires toxicity to insectswhich consume its edible portions.

The concentration of toxic material in our insecticidal compositionswill depend on many factors, such as the particular toxic material ormaterials which are used, the carrier used, the method and conditions ofapplication, the insect species to be controlled, etc., the properconsideration of these factors being within the skill of those versed inthe art. In general, the toxic materials hereinbefore-described will beetfective in concentrations of from about 0.01% to about 0.5% by weight,based upon the total weight of the composition, although, depending uponthe circumstances, as little as about 0.001% or as much as 2% or evenmore of the toxic material may be employed effectively.

In our new compositions, the toxic agents hereinbeforedescribed may beemployed as the sole toxic ingredient, or they may be employed inconjunction with other insecticidally active materials. Such otherinsecticidally active materials include, without being limited to, thenaturally occurring insecticides, such as pyrethrum, rotenone,sabidilla, and the like, as well as synthetic materials such ascompounds of arsenic, lead, and/ or fluorine;

DDT, benzene hexachloride, thiodiphenylamine, cyanides,

0,0-diethyl-O-p-nitrophenyl thiophosphate, azobenzene, and the like. 1

Particularly suitable compound of the invention for use in theinsecticidal compositions of the invention are the following:

0,0-diethyl S-2-acetoxyethyl phosphorothiolate C HEO 0,0-dimethylS-2-pr0pionyloxyethyl phosphorodithioate CH O\fi P-SOH2CH;OC(0)CH2CH3 CHO these being typical species of subgenus (1) described in column 3;

0,0-diethyl S-2-chloro-2-acetoxyethyl phosphorothiolate 16 0,0-diethylS-3-acetoxy-2-chloropropyl phosphorothiolate zHaO O P-S-CH;CCl-CHz-OC(O)-CH3 (321150 these being typical species of subgenus (2) described incolumn 3;

0,0-diethyl S-3-acetoxy 2 chloroprop-l-enyl phosphorothiolate zHaO 0,0diethyl S-3-acetoxy-2-chloro-3-phenylprop-l-enyl phosphorothiolate ZHsO0 and these being typical species of subgenus (3) described column 3;

All these compounds are at least as toxic as the known insecticidesmethyl parathion (MP) to red spider mites, Tetranychus telarius (Linn.)and some are considerably more active, as can be seen from Table IV,where the figures in the second row of the last column denote thetoxicities relative to methyl parathion. 0,0-diethyl S-2- acetoxyethylphosphoroth-iolate, which is eight times as active as methyl parathionagainst red spider mites and kills all the insect species tested, is aparticularly useful compound, so also is 0,0-dimethylS-Z-propionyloxyethyl phosphorodithioate, which is not only twice asactive as methyl parathion against red spider mites but also highlyselective in its action, being active only on mosquito larvae of theremaining test insects.

The formulation and use of insecticidal compositions of this inventionis illustrated in the following examples, which illustrate thepreparation and use of typical insecticidal compositions of thisinvention.

EXAMPLE 23 A 1% by weight solution in acetone of each of the chemicalsobtained in the previous examples was prepared.

The solution was applied topically to twenty adult female house fiies,Musca domestica, at the rate of 1 milliliter of solution per fly.

To milliliters of water containing 0.1 milliliter of the test solutionwere added twenty mosquito larvae, Aedes aegypti (yellow fevermosquito).

Hardened filter paper, 9 centimeters in diameter, was placed in a petridish and evenly impregnated with 1 milliliter of the test solution andthe solvent allowed to evaporate. Five adult male German cockroaches,Blatella gernmnica, were exposed to one paper, and ten adult flourbeetles, Tribolium canfusum, to another.

In tests against diamond-back month larvae, Plutella maculipennis(Curtis), and pea aphids, Acyrthosiphon pisum (Harns), turnip and broadbean plants, trimmed to one leaf each, were sprayed on the under surfaceof the leaf with a 1.6% by weight suspension of the chemical in a 0.25%by weight aqueous solution of Triton X 100 as wetting agent, prepared ina micro-wet grinder. Spraying was effected with a paint-type spray gundelivering 17 gallons per acre at 50 pounds per square inch pressure,the plants passing under the spray on a moving belt. Ten moth larvae andten aphids respectively were placed on the sprayed leaves and each plantthen enclosed in a glass cylinder fitted at one end with a muslin cap.

In tests against rcd spider mite, T etranychus telarius (Linn), discs 6centimeters in diameter cut from previously infested French bean leaveswere placed on damp v and bean plants.

For comparative purposessimilar tests were carried out against redspider mite using the standard insecticidev methyl parathion (MP).

acyl represents the acyl moiety of a mononuclear aromaticv hydrocarbonsulfonic acid of from 6 to 6. The ester having the formula;

' alkyl- 0' 10 carbon atoms.

In all these tests, mortality counts were made 24 and P S R O acyl v 48hours later. The results of these tests are summarized R-Q in thefollowing table, where A denotes 100% kill, and B wherein R representsnitro-substituted phenyl, alkyl repdenotes some kill. resents alkyl offrom 1 to 8 carbon atoms, R represents TABLE IV Insect Name of ChemicalMusca Blatella Trzbolium Aeries Plutella Acyrtho- Tetranydomesticagermam'cu ctmfusum aegypti maculisiphon chus larvae penm's pisumtelarius 0,0-diethy1 S-Z-acetoxyethyl phosphorothiolate l A A A A A A 8XAMP 0,0-dimethyl S-2-propiony1oxyethyl phosphorodithioate A C O 2 XAMP0,0-diethyl S-2-chloro-2-acetoxyethyl phosphorothiolate A A A B O A 1 MP0,0-diethy1S-S-acetoxy-2-ch10roprop-l-eny1phosphorothiolate A A A B B V1 XAMP 0,0-diethyl S 3-acetoxy-Z-ohloro-ii-phenylprop-1-enyl .phos- A AA B B A A phorothiolate. 1 X MP 0,0-diethy1 S-3-aeetoxy-2-ch1oropropy1ph0sphorothi01ate A A A B B A 1 5AM]? O-Ethyl O-p-m'trophenylS-2-ohloro-2-propionyloxyethy1 B 1 B 1 A 2 A 2 z A 2 phosphorothiolate.O-Ethyl O-2,4-dieh1orophenylS-2-ehloro-2-propionyloxyethyl A 2phosphorothiolate.

1 In these tests, the dosage was one-tenth of the dosage used in theprevious tests. 2 In these tests, the dosage was two-sevenths of thedosage used II]. the previous tests.

I claim as my invention: 1. The ester having the formula:

wherein R represents a member of the group consisting of alkyl from 1 to8 carbon atoms, phenyl, nitro-substituted phenyl and halogen substitutedphenyl, R contains up to carbon atoms and is a member of the groupconsisting of alkenylene and halogen-substituted alkenylene, and acylrepresents the actyl moiety of an acid of the group consisting ofalkanemonocarboxylic acids of up to 4 carbon atoms, mononuclear aromatichydrocarbon monocarboxylic acids of from 6 to 10 carbon atomsandmononuclear aromatic hydrocarbon sulfonic acids of from 6 to 1-0carbon atoms, and X represents a member of the group consisting ofoxygen and sulfur.

2. The ester having the formula of claim 1 wherein X represents oxygen,R represents alkyl of from 1 to 8 carbon atoms, R is alkenylene of up to10 carbon atoms and acyl is the acyl moiety of an alkanemonocarboxylicacid of up to 4 carbon atoms.

3. The ester having the formula ,of claim 1 wherein X haloalkylene of upto 10 carbon atoms, and acyl repre sents the acyl moiety of analkanemonocarboxylic acid of up to 4 carbon atoms.

7. The ester having the formula:

alkyl-O 0 represents the acyl moiety of an alkanemonocarboxylic acid ofup to 4 carbon atoms.

8. O-ethyl O-p-nitrophenyl S-2-chloro-2-propiony1oxyethylphosphorothiolate.

9. ;O-ethyl O-=2,4-dich1orophenyl S-2-chloro-2-propionyloxyethylphosphorothiolate.

represents oxygen, R represents alkyl of from 1 to 8 carbon atoms, R isalkylene of up to 10 carbon atoms and acyl represents the acyl moiety ofa mononuclear aromatic hydrocarbonsulfonic acid of from 6 to 10 carbonatoms.

4. The ester having the formula of claim 1 wherein X represents sulfur,R represents alkyl of from 1 to 8 carbon atoms, R is alkenylene of up to10 carbon atoms, and

acyl is the acyl moiety of a lower alkanemonocarboxylic acid.

5. The ester having the formula of claim'l wherein X represents sulfur,R represents alkyl of from 1 to 8 car- 7 bon atoms, R is alkylene of upto 10 carbon atoms and References Cited by the Examiner UNITED STATESPATENTS 2,862,019 11/58 Schrader 260-461 2,912,450 11/59 McConnell'etal. 260-461 2,945,053 7/ 60 I McConnell. et al. 260- 461 2,947,775 8/60Coover et al. 260-461 OTHER REFERENCES Melnikov et al.: Chem. Abst.,vol. 48, col. 556-557 (1954).

Gar et al.: Chem, Abst., vol. 48, col. 6639 (1954). Melnikov et al.: J.Gen. Chem. U.S.S.R.- (English trans), vol. 23, pp. 1417-1420(a) (1953.

Paikin et al.: Chem. Abst., vol. 42, col. 4096-4097 Mastryukova:

Chem. Abst., vol. 51, col. 1844-1 (1957). V

CHARLES B. PARKER, Primary Examiner.

MORRIS LIEBMAN, Examiners.

1. THE ESTER HAVING THE FORMULA: